Food Technology

What Are Food Additives? Definitions and Scope

A food additive is any substance deliberately added to a food during production, processing, packaging, or storage to perform a specific technological function. Under the Australia New Zealand Food Standards Code (the Food Standards Code), administered by Food Standards Australia New Zealand (FSANZ), additives are strictly regulated to ensure they are safe, necessary, and used only in quantities that achieve their intended purpose — the principle of minimum effective concentration.

The Food Standards Code distinguishes food additives from processing aids (substances used during manufacture but not present in the final food in significant amounts), nutritive substances (vitamins, minerals), and contaminants. Additives must be listed on food labels by their class name followed by either the additive's specific name or its International Numbering System (INS) number — for example, Preservative (202) for potassium sorbate. This labelling requirement under Standard 1.2.4 enables consumer transparency and informed choice.

It is essential to understand that not every additive is permitted in every food — Standard 1.3.1 (Food Additives) specifies permitted additives by food category, the maximum permitted level (MPL), and the specific technological purpose. An additive may be approved in bread but not in infant formula, reflecting a risk-based approach that applies stricter limits where vulnerable populations are involved.

Preservatives: Extending Shelf Life and Preventing Spoilage

Preservatives (class name: Preservative) inhibit the growth of micro-organisms such as bacteria, yeasts, and moulds, or slow chemical deterioration that would make food unsafe or unacceptable. They are one of the most commercially important additive classes because they directly extend shelf life, reduce food waste, and support safe distribution across extended supply chains.

Key preservatives under the Food Standards Code include:

• Sulfites/sulphur dioxide (INS 220–228): Used in dried fruit, wine, and fruit juices. They inhibit enzymatic browning and microbial growth. However, they can trigger asthma in sensitive individuals — hence the mandatory declaration requirement when sulfites are present at ≥10 mg/kg. This is a mandatory allergen/sensitivity disclosure.
• Sorbic acid and sorbates (INS 200–203): Effective against yeasts and moulds at mildly acidic pH. Found in cheese, bakery products, and processed meat. Potassium sorbate (202) is widely used because it is water-soluble and considered low-toxicity.
• Benzoic acid and benzoates (INS 210–213): Active in acidic foods (pH below 4.5); used in soft drinks, pickles, and condiments. Concerns have been raised about a combination of sodium benzoate and certain colours (tartrazine, sunset yellow) being linked to hyperactivity in children — the FSANZ review concluded evidence was insufficient to ban these in Australia but recommends caution, reflecting the precautionary principle.
• Nitrites and nitrates (INS 249–252): Used in cured meats (bacon, ham, smallgoods) to prevent Clostridium botulinum growth, fix the characteristic pink colour, and contribute to flavour. Permitted maximum levels in Australia are strictly limited because excess nitrite can form nitrosamines, which are carcinogenic.

Applied example: Metcash's Australian grocery supply chain ships smallgoods from processors in South Australia to retailers in northern Queensland. Without sodium nitrite (INS 250), C. botulinum could produce deadly botulinum toxin under the anaerobic conditions of vacuum packaging during the multi-day transit. The permitted level of 125 mg/kg for cooked cured meats balances safety against health risk, reflecting FSANZ's risk–benefit analysis process.